Piston-type internal combustion engines involve marked vibrations attendant with the reciprocation of the piston and have the additional problem that the cylinder can not be thoroughly scavenged unless the exhaust valve is opened near the end of the combustion process an overlapping relation thereto, before the initiation of the exhaust or scavenging stroke. However, this prevents complete combustion of the fuel, contributing to reduced thermal efficiency.
Gas turbine engines are substantially free of the above problems encountered with piston-type engines since the combustion gas supplied from a combustor through a conduit is forced at a high velocity against a wheel provided with rows of blades over the entire periphery thereof to drive the wheel. However because the fuel must be continuously injected into the combustion chamber while the engine is in operation, the engine requires greater fuel consumption than piston-type engines. Additionally the necessity of supplying pressurized air to the combustor at a constant compression ratio at all times entails the problem of supplying a powerful blower and a special combustor.